The present invention relates to a form panel system for forming concrete walls and the like and, more particularly, is directed to such a system employing an improved tie rod assembly for securing modular form panels in place. The invention is especially concerned with an assembly wherein the tie rods are of a length less than the distance between opposed form panels and the tie rod assembly may be fed into place through the panels.
In most conventional tie rod assemblies for securing form panels in opposed spaced relationship, the tie rods have a length greater than the distance between the panels and some type of gripper is employed to grip the ends of the tie rods externally of the concrete. In such systems, the tie rods may be of the "snap-tie" or "she-bolt" type and, after the concrete has set, the ends of the rods are either broken off or unscrewed somewhere inside the concrete.
The prior art also teaches the use of tie rods having a length less than the distance between opposed form panels. Such teachings may be found in U.S. Pat. Nos. 871,390; 2,726,432; and 3,965,542. The tie rods and the gripping assemblies therefor shown in these patents are not, however, facilitated for "feed-through" placement from one side of the form panels in the manner of the present invention.
The present invention is also concerned with an arrangement for securing adjacent modular form panel elements in edge to edge engagement. This is achieved by employing the tie rod gripping assembly as part of the structure to secure the elements together. U.S. Pat. No. 3,910,546 discloses a structure for securing adjacent form panel elements in edge to edge engagement, but in the structure of this patent the securing means is separate from the tie rod engaging mechanism.